package com.itheima.reggie.web;


import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.UUID;

@RestController
@RequestMapping("/common")
@Slf4j
public class CommonController {

    @Value("${reggie.path}")
    private String basePath;

    //上传图片方法
    @PostMapping("/upload")
    public R<String > upload(MultipartFile file){
        //file是一个临时文件，需要转存到指定位置，否则本次请求完成后临时文件会删除
        //原始文件名
        String originalFilename = file.getOriginalFilename();//***.jpg
        //截取文件名后缀   .jpg
        String suffix = originalFilename.substring(originalFilename.lastIndexOf("."));
        //使用UUID重生成文件名，防止文件名重复造成文件覆盖
        String filename = UUID.randomUUID().toString()+suffix;
        //创建一个目录对象
        File dir = new File(basePath);
        //判断当前目录是否存在,不存在的话，创建一个目录
        if (!dir.exists()){
            dir.mkdirs();
        }
        //将临时文件转存到指定位置
        try {
            file.transferTo(new File(basePath+filename));
        } catch (IOException e) {
            e.printStackTrace();
        }
        return R.success(filename);
    }

    //下载图片方法
    @GetMapping("/download")
    public void download(String name, HttpServletResponse response){
        //通过输入流读取文件内容
        try {
            FileInputStream fileInputStream = new FileInputStream(new File(basePath+name));
            //通过输出流将文件写回浏览器
            ServletOutputStream outputStream = response.getOutputStream();
            //设置响应回去的文件类型
            response.setContentType("image/jpeg");

            int length = 0;
            byte[] bytes = new byte[1024];
            while ((length=fileInputStream.read(bytes))!=-1){
                outputStream.write(bytes,0,length);
                outputStream.flush();
            }
            //关闭资源
            outputStream.close();
            fileInputStream.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}
